Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet
Product codes
AT91SAM9M10-G45-EK
1314
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
47.14 DDRSDRC Timings
The DDRSDRC controller satisfies the timings of standard DDR2, LP-DDR, SDR and LP-SDR modules.
DDR2, LP-DDR and SDR timings are specified by the JEDEC standard.
Supported speed grade limitations:
• DDR2-400 limited at 133MHz clock frequency (1.8V, 30pF on data/control, 10pF on CK/CK#)
• LP-DDR (1.8V, 30pF on data/control, 10pF on CK)
Tcyc = 5.0 ns, Fmax = 125 MHz
Tcyc = 6.0 ns, Fmax = 110 MHz
Tcyc = 7.5 ns, Fmax = 95 MHz
Tcyc = 6.0 ns, Fmax = 110 MHz
Tcyc = 7.5 ns, Fmax = 95 MHz
• SDR-100 (3.3V, 50pF on data/control, 10pF on CK)
• SDR-133 (3.3V, 50pF on data/control, 10pF on CK)
• LP-SDR-133 (1.8V, 30pF on data/control, 10pF on CK)
47.15 Peripheral Timings
47.15.1
SPI
47.15.1.1
Maximum SPI Frequency
The following formulas give maximum SPI frequency in Master read and write modes and in Slave read and write
modes.
modes.
Master Write Mode
The SPI is only sending data to a slave device such as an LCD, for example. The limit is given by SPI
2
(or
SPI
5
) timing. Since it gives a maximum frequency above the maximum pad speed (see
the max SPI frequency is the one from the pad.
Master Read Mode
T
valid
is the slave time response to output data after deleting an SPCK edge. For Atmel SPI DataFlash
(AT45DB642D), T
valid
(orT
v
) is 12 ns Max.
In the formula above, F
SPCK
Max = 38.5 MHz @ VDDIO = 3.3V.
Slave Read Mode
In slave mode, SPCK is the input clock for the SPI. The max SPCK frequency is given by setup and hold tim-
ings SPI
ings SPI
7
/SPI
8
(or SPI
10
/SPI
11
). Since this gives a frequency well above the pad limit, the limit in slave read
mode is given by SPCK pad.
Slave Write Mode
For 3.3V I/O domain and SPI6, F
SPCK
Max = 33 MHz. T
setup
is the setup time from the master before sampling
data.
47.15.1.2
Timing Conditions
Timings are given assuming a capacitance load on
MISO, SPCK and MOSI
:
f
SPCK
Max
1
SP I
0
orSPI
3
(
) T
valid
+
----------------------------------------------------------
=
f
SPCK
Max
1
SPI
6
orSPI
9
(
) T
setup
+
----------------------------------------------------------
=